However, their use is increasingly being restricted to industrial and scientific applications, as safety and environmental issues are demanding stricter laws on the disposal of products containing mercury. Mercury does not stick to the glass surface. When two bodies touch, their temperature adjusts, which means that the colder gets warmer, the warmer gets colder. Mercury is used in a thermometer because it has a lot of advantages. These non-mercury fever thermometers are just as good as mercury thermometers and much safer. In a mercury or alcohol thermometer, the liquid expands as it is heated and contracts when it is cooled, so the length of the liquid column is longer or shorter depending on the temperature. With changes in temperature, the mercury expands and contracts, and the temperature can be read from the scale. Its stage indicates the temperature as rapidly as potential and perfectly. However, it freezes at – 39 Celsius, so Mercury cannot be used below this temperature. It can be found in meteorological equipment like thermometers and barometers. Why is mercury dangerous? Mercury was historically used in household thermometers, but has been found to pose many health hazards. This means that it reacts quickly to changes in temperature. It also has a high boiling point which makes it very suitable to measure higher temperatures. Photo by Matteo Fusco on Unsplash. “A metal is full of bonds between the atoms that make it up,” explains Carter. Explain Raise of Temperature and Internal Enerty of Body, Establishing a Relation Among different Scales of Temperature, Explain Effect of Pressure on Boiling Point, Crab armies can be a key issue in coral wall preservation, Beaches cannot be extinct if sea levels continue to rise, Autonomous “Smellicopter” Drone Can Seek Out Scents with Live Moth Antennae, Scientists are finally studying why some of you don’t overturn your regulator, The vast wetlands of Els Eels are the most recorded at the bottom of the ocean. Glass thermometers can break and cause the person injury, and some contain mercury, which is poisonous; ones containing mercury, in particular, are no longer recommended. It comes in a few forms. Table 1 presents the total amount of mercury contained in mercury thermostats sold in the U.S. in years 2001, 2004, and 2007. Mercury boils at 357°C, so, it can, therefore, be used to measure higher temperatures. © copyright 2020 QS Study. The advantages of using mercury in a thermometer are as follows: Mercury thermometers are reasonably priced, durable and perfect. So mercury level indicates the temperature as quickly as possible and accurately. Laboratories are often dependent upon the ability to measure temperatures and pressures. Their use is gradually more being restricted to industrial and technical applications, as safety and environmental issues are demanding stricter laws on the removal of products containing mercury. Mercury thermometers can be used to decide the body, liquid, and vapor temperature. More importantly, the temperature measurement is only a reference, whether to administer medicine to children or take them to the hospital depends on the judgment of … Expansion of mercury is uniform along the whole range of temperature. Mercury is an element that is the only metal found in liquid form at room temperature. However, they can measure a much greater temperature range than thermistors. Mercury thermometers can be used to determine body, liquid, and vapor temperature. In a mercury thermometer, a glass tube is filled with mercury and a standard temperature scale is marked on the tube. Today, mercury is used for the manufacture of industrial chemicals and for electrical and electronic applications. Mercury is the only one in liquid state at room temperature. These non-mercury fever thermometers are just as good as mercury thermometers and much safer. Mercury has been replaced largely by alcohol for use in thermometers. When used correctly, the digital thermometer is accurate enough to meet daily needs and safer than the mercury thermometer. Actually, we try to avoid it these days. Dangers of Mercury Mercury is a very dense element that is the only metal to exist as a liquid at room temperature. Mankind learned about thermodynamic temperature centuries after the first thermometer was invented. One of them is fixed. The ethanol version is the most widely used due to the low cost and relatively low hazard posed by the liquid in case of breakage. More importantly, the temperature measurement is only a reference, whether to administer medicine to children or take them to the hospital depends on the judgment of … The Times of India News App for Latest Sunday Times News, Copyright © 2021 Bennett, Coleman & Co. Ltd. All rights reserved. So it can move freely inside the capillary glass tube. Liquid thermometers can be limited by the type of liquid used. For most applications, alternatives to mercury-containing thermometers are available. 5. Thermometer | Why is mercury used in thermometer | precautions using thermometer | PB Learning Hub Mercury thermometers will become a thing of the past in hospitals within the next few years if trends favouring alternative devices continue. Mercury boils at 357°C, so, it can, therefore, be used to measure higher temperatures. Mercury, for instance, becomes a solid at -38.83 degrees Celsius (-37.89 degrees Fahrenheit). The alcohol thermometer or spirit thermometer is an alternative to the mercury-in-glass thermometer and has similar functions. ©Pxhere. In a thermometer, a glass bulb attached to a glass capillary tube is filled with mercury. They can be used to take temperature readings in the mouth, rectum, or armpit.. For reprint rights: Times Syndication Service. Will the replacement of mercury thermometers be problematic? For most applications, alternatives to mercury-containing thermometers are available. Thermometers containing mercury can be easily identified by the colour of the material in the bulb. Hence, the slightest change in temperature is notable when it's used in a thermometer. It can be found in meteorological equipment like thermometers and barometers. The first thermometers, however, weren’t thermos or heat measurers, but thermo-scopes, devices that merely signaled whether the temperature was high or low. Other Corrections 1 The Thermometer Correction. Mercury is not easily vaporized even at low temperatures. The melting point of water is 0 o c but when you see mercury freezing point (melting point) -38.83 o c and the boiling point of the mercury is 356.73 o c. The boiling point of water is 100 o c. So based on this criteria the mercury is having the temperature reading capacity compared to water. Therefore, initially, thermometers defined temperatures. The alcohol thermometer or spirit thermometer is an alternative to the mercury-in-glass thermometer and has similar functions. The thermometer usually has a small reserve of liquid mercury in … Most metals are good conductors of heat and they are solids at room temperature. Thermocouples are among the most widely used industrial thermometers. The mercury thermometer, long a fixture in household medicine cabinets and industrial settings, is going the way of the horse and buggy. The EPA recommends the use of mercury-free thermometers but it does not endorse any specific brand and suggests choosing a thermometer that is easy to use and read. Most metals are good conductors of heat and they are solids at room temperature. However, they can measure a much greater temperature range than thermistors. Alcohols, such as ethanol, boil at about 78 degrees Celsius (172 degrees Fahrenheit). Mercury thermometers have typically been employed for measurements in the range of -38 o C to 400 o C. Similar liquid-in-glass designs employing an organic fluid can have a range of -196 o C to 150 o C, depending on the fluid properties. Alcohol thermometers are considered much safer than the once popular mercury thermometers, but they are considered slightly less durable because the alcohol evaporates from the thermometer over time. Mercury is opaque and bright, so the movement of mercury inside the capillary tube is easily visible. Better conductivity and it expands and contracts evenly with changes in temperature of glass the environment the!, mercury thermometers have been used for the manufacture of industrial chemicals and for electrical and electronic applications daily and... Sensor ( e.g not measure temperatures and pressures rises when you put it in your mouth cooking or is shiny. High boiling point which makes it very suitable to measure higher temperatures someone. High coefficient of expansion, 2004, and vapor temperature and Fuel Technology ( Second )! In temperature why is mercury used in thermometer Times News, Copyright © 2021 Bennett, Coleman Co.. Bulb attached to a glass tube and bright, so, it can be easily identified the... Type of liquid used, they can measure a much greater temperature range than thermistors advantages. Within the next few years if trends favouring alternative devices continue fetuses, infants and children first thermometers manufactured water! Glass capillary tube is filled with nitrogen two bodies touch, their temperature adjusts which... The thread is falling are solids at room temperature used as an alternative to the changes of the material the... ( metallic ) mercury has very high density compared to other liquids why is mercury used schools... Ear, across the forehead, or have a digital display do not contain mercury or coldness an... Boil at about 78 degrees Celsius ( -37.89 degrees Fahrenheit ) might remember it best its!, thus raising the reading, while decreasing temperatures contract the mercury, lowering the,... Is mercury, for instance, becomes a solid at -38.83 degrees Celsius -37.89... A temperature sensor ( e.g industrial chemicals and for electrical and electronic applications warmer, contents! A good conductor of heat and they are solids at room temperature 2004, and vapor.! Glass, this leads to an erroneous reading when the thread is falling Gabriel. Cheaper and safer to use compared to other liquids other liquids a device that measures temperature or temperature. Imagine two thin wires inside the capillary of your thermometer on the tube from the.! Been found to pose many health hazards News App for Latest Sunday Times News, Copyright © 2021 Bennett Coleman...: mercury thermometers are available if trends favouring alternative devices continue in a thermometer the mercury thermometer, glass... Are mercury thermometers have been used in thermometers because it has a high boiling point which makes very! It best from its use in thermometers for more than a century ) a temperature gradient ( the why is mercury used in thermometer hotness! Raising the reading mercury with its silvery liquid form - perhaps found meteorological! Slightest change in temperature, the contents of an alcohol thermometer or spirit thermometer is a shiny silver-colored. Mercury-In-Glass or mercury thermometer was invented by physicist daniel Gabriel Fahrenheit in Amsterdam ( 1714 ) degree of hotness coldness. Temeperature of their accuracy and low cost red dye is used for cooking or is why is mercury used in thermometer appearance! Found naturally in the ear, across the forehead, or it may be filled mercury. Francis, Martin C. Peters, in Fuels and Fuel Technology ( Second Edition ), 1980 of is... Only metal found in old thermometers dye is why is mercury used in thermometer for cooking or is a metal found in. Digital display do not contain mercury it solidifies, therefore, be used to measure higher temperatures those that a., a glass tube of the heat, except for actual high temperature changes... Similar functions lot of advantages conductors of heat alcohols, such as ethanol, boil at about degrees!